The Identification Of Fermentative Bacteria From Petroleum Reservoirs And Anaerobic Metabolic Mechanism Of Crude Oil Hydrocarbon

Using a variety of technical means was to detect the biological and geochemical characteristics of the enrichment at different times and analysis the influencing factors in the process of anaerobic biodegradation of petroleum hydrocarbon. We also isolated two thermophilic fermentative bacteria from petroleum reservoirs and studied the physiological characteristics and phylogenetic position of the two strains.The results were as follows: (1) Different temperatures and metabolic pathways influenced the communities. The bacterial communities had more pronounced changes than archaeaen communities; (2) With the culture time increased, acetate content lower and methane content increased. More methane was generated under 55℃than 35℃; (3) At sulfate-reducing condition, SO42- content was decreased. Crude oil Luo made use of more SO42- than crude oil Zhong; (4) The n-alkanes of crude oil Luo was decreased greater at 35℃than 55℃. The n-alkanes of crude oil Luo was decreased greater in methanogenic condition than that of sulfate condition; (5) The naphthalene and phenanthrene of crude oil Zhong had been degraded. Alkyl naphthalene was decreased greater by sulfate-reducing way; (6) The naphthalene and phenanthrene of crude oil Luo show the same trends as n-alkanes in anaerobic degradation; (7) TheΣC21-/ΣC22+ became larger while Pr/Ph ratio became smaller. The anaerobes may use long-chain alkane and Pr in advance; (8) Strain 2SM-2 was strictly anaerobic. Optimum growth temperature, pH and NaCl concentrations were 65℃, 7.0 and 15 g l-1. The glucose fermentation product were acetate, lactic acid, L-alanine, a small amount of H2 and CO2. Identification of Thermococcoides shengliensis gen.nov, sp.nov 2SM-2T, a new genus belonging to the order Thermotogales, was the first report domesticly.